From mboxrd@z Thu Jan  1 00:00:00 1970
From: Panu Matilainen <pmatilai@redhat.com>
Subject: Re: [PATCH] eal: fix plugindir processing to be
 filesystem agnostic
Date: Mon, 23 Nov 2015 08:04:10 +0200
Message-ID: <5652AC5A.4080005@redhat.com>
References: <923ebe527219fa16ca91e74b416b978803056d70.1447829123.git.pmatilai@redhat.com>
 <CALwxeUt5-hD+Y0KWVhBJNY0nWq-ZRVx_F06gaaAphxsW_+1LBg@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
Cc: "dev@dpdk.org" <dev@dpdk.org>
To: David Marchand <david.marchand@6wind.com>
Return-path: <dev-bounces@dpdk.org>
Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28])
 by dpdk.org (Postfix) with ESMTP id 8C0558E7E
 for <dev@dpdk.org>; Mon, 23 Nov 2015 07:04:12 +0100 (CET)
In-Reply-To: <CALwxeUt5-hD+Y0KWVhBJNY0nWq-ZRVx_F06gaaAphxsW_+1LBg@mail.gmail.com>
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

On 11/20/2015 06:38 PM, David Marchand wrote:
> Hello Panu,
>
> On Wed, Nov 18, 2015 at 7:45 AM, Panu Matilainen <pmatilai@redhat.com>
> wrote:
>
>> Not all filesystems supply struct dirent d_type field, in which case
>> everything in the specified directory would go ignored. One such
>> filesystem being XFS which RHEL 7 defaults to... stat() the entries
>> instead.
>>
>> Fixes: 9f8eb1d9ca0f ("eal: support driver loading from directory")
>>
>> Signed-off-by: Panu Matilainen <pmatilai@redhat.com>
>> ---
>>   lib/librte_eal/common/eal_common_options.c | 6 ++++--
>>   1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/lib/librte_eal/common/eal_common_options.c
>> b/lib/librte_eal/common/eal_common_options.c
>> index bed7385..e51fa12 100644
>> --- a/lib/librte_eal/common/eal_common_options.c
>> +++ b/lib/librte_eal/common/eal_common_options.c
>> @@ -191,12 +191,14 @@ eal_plugindir_init(const char *path)
>>          }
>>
>>          while ((dent = readdir(d)) != NULL) {
>> -               if (dent->d_type != DT_REG && dent->d_type != DT_LNK)
>> -                       continue;
>> +               struct stat sb;
>>
>>                  snprintf(sopath, PATH_MAX-1, "%s/%s", path, dent->d_name);
>>                  sopath[PATH_MAX-1] = 0;
>>
>> +               if (!(stat(sopath, &sb) == 0 && S_ISREG(sb.st_mode)))
>> +                       continue;
>> +
>>                  if (eal_plugin_add(sopath) == -1)
>>                          break;
>>          }
>
>
>
> It looks like you would skip the symbolic links while you were not before.
> Intended ?

Intended. We want to accept symlinks in the driver directory, but the 
actual drivers are always regular files. Since stat() dereferences 
symbolic links it cannot return a file whose type would be S_IFLNK.

	- Panu -